Drying apparatus



Oct. 1 1935. R. R. sNow lamme-'APPARATUS Filed Feb. 11, 1955 2Sheets-Sheet l Oct. 1, 1935. R. R. SNOW DRYING APPARATUS Filed Feb. ll,1935 2 She'ets-Sheet 2 ROBERT R. 5A/0 W.

ATTORNEYS,

lPatented Get. 1, v1935A DRYING APPARATUS .Robert R. Snow, Holly, Mich.,assigner to Chrysler Corporation, Detroit, Mich., a corporation ofDelaware Application February 11, 1935, serial No. 6,031

10 Claims.

This invention relates to a drying apparatus.v

While the embodiment of the invention is herein illustrated anddescribed in connection with the drying of green sand molds, it shouldbe understood that the invention is not to be so limited but may be usedfor a similar purpose in connection with various articles of Vdifferentshapes and mass.

It is common practice in connection with green sand molds to treat theinternal surface with a solution forming a skin which lis subsequentlydried. Heretofore the practice has been to pass molds so washed througha drying oven and to later complete the drying of the surfaces by amanually directed torch. In oven drying the entire surface of the'moldis exposed to a constant application of heat, frequently resulting inblistering due to the generation of steam faster than it can escapethrough the sand and pores of the skin.

An object of the inventionis to provide an apparatus adapted to dry theskin on molds evenly throughout the entirey molding surface Withoutblistering or otherwise injuring the skin or other portions of the mol-dstructure.

Another obj ect of the invention is to provide an apparatus of this kindwhich applies heat at one time to localized areas of the surface of themold.

A further object of the invention is to provide an apparatus which iscompletely automatic in its operation and adapted to accuratelypredetermine the length of time all portions of the mold surface areexposed to the drying action.

A still further object of the invention is to provide means forcontrolling the application of heat to an article which is soconstructed and arranged as to operate uniformly and consume fuel onlywhen the article is suitably positioned with respect to the dryingapparatus.

A further object of the invention is to provide fully automatic dryingmechanism of this character which does not require manual attention ofany kind and in the operation of which variations incidental to the.human element involved in manual control are completely eliminated.

Other objects of the inventionare to provide a heatproducing elementwherein the supply of fuel thereto is controlled by progressive movementof the Work within the drying area of the heating element; to provideapparatus l of this kind which includes a plurality of intermittentlyburning, oscillatably mountedy heating elements,

and control mechanism for each element which' may be adjusted topredetermine the period during which such elements are' operative; t0providev control mechanism of this character which is adapted toinitiate the operation of a heating element after any selected portionof an article has passed thereby and to discontinue the operation ofsuch a heating element before any se- 6 lected portion of the articlehas passed from` Within the effective range of the heating element, andto provide a single means for oscillating the heating elements which maybe adjusted to predetermine the lengths of the arcs of 10 movementthereof.

The apparatus herein described has been found particularly adaptable inthe drying of green sand molds which have been washed with a solutionto4 provide a skin, and it embodies a series of 15 spaced mechanicallyoscillated torches arranged above a conveyor mechanism. Each torch iscontinuously oscillated and intermittently supplied with gas and airunder pressure controlled by a valve mechanism operable by contact withthe 20 mold as the. latter is moved under the torch by. the conveyor.vits the mold passes under a particular torch it contacts a valvecontrol member which opens the valve mechanism admitting a fuel mixtureto the associated torch and the latter 25 is ignited by a continuouslyburning pilot light. The surface of the mold is then swept by successiveoscillations of the torch during the period the valve mechanism isretained in open position by the moving mold. ',I'he period between the30 application of heat from successive torches permits the generatedsteam to escape from the mold and prevents blistering of the skinwhich', in practice,l frequently results from the accumulation of steambeneath the skin. The torch iiame can be 35 adjusted for use on'articles of different shapes and masses so as to control the intensityof heat and the length of the strokes thereof may be varied to conformwith the dimensions of articles of diverse sizes and shapes. Any loosesandor 40 dirt collected on the mold surface is blown from the cavitiesthereof by the force of the llame created by fuel supplied underpressure. Y

An illustrative embodiment of the invention is shown in the accompanyingdrawings, in which: 45

Fig. 1 is a side elevational view of a drying apparatus embodying theinvention. 1

Fig. 2 is o. fragmentary, horizontal sectional view taken on the line2-2 of Fig. 1.

Fig. 3 is a night end elevational view illustrat- 50 ing the apparatusshown in Fig. 1 as viewed from lines 3-3 thereof.

In the form shown in the drawings, the drying apparatus includes asupporting structure, generally designated by the numeral 5, which 55structure comprises upright posts I0, upper and lower cross members I2and I4, respectively, andA an intermediate horizontally extendingoscillatably mounted shaft I6, journaled in bearings I1. Mounted on theupper cross members I2 is a .driving motor I8 which is operativelyconnected The other end of the rod 28 is pivotally attached to a crankarm 30 fixed to one endr of the shaft I6. The length of the arc ofoscillatory movement of theshaft I6 may be varied by adjust-V ing thearm 21 relative to the axis of the disc 24 whereby the effective lengthof the rod 28 is increased or decreased to correspondingly alter thelength of the oscillatory stroke.

The heating elements each preferably com.- prises a torch 32 which isfixed by means of a bracket 34 to the shaft I6 for oscillationtherewith. While any number of such torches may be employed, theconstruction and operation is the same and only one is herein describedfor the purpose of illustrating the invention. Air and gas, constitutingthe fuel, are supplied to the torch by means of vertically positionedconduits IIB/and 42, respectively, the lower adjacent ends thereof beingconnected with a suitable source of supply of gas and air, respectively,and

.-1 the upper adjacent ends being connected by sections of flexible hose44 and 46 with bifurcated end portions36 and 38, respectively of thetorch. The conduits 40 and 42 are secured by U-bolts 48 to a mountingplate 5i), the latter being fixed to the lower part of the supportingstructure 5.

Passage of fuel through the conduits 40 and 42 ls controlled by anindividual valve 52 of the whistle type, each valve being provided witha rotatable.c'ontrol arm 54 adapted for operation by a rod 56 and partscarried thereby shiftably supported by the plate 5D. "Ihe rod 56 isurged to the right, as viewed in Fig. 2, by a coil spring 553, one endof which is provided with a hook received in an eye of the rod 56, theother end thereof being fixed to one of the upright posts I0. Adjustablyfixed on the rod 56 are a plurality of stops 62 and a pair of coilsprings 64, one of such springs being positioned between a stop 62 andan arm 54 so as tof urge the latter Iin a clockwise direction, as viewedin Fig. 2, and y to maintain the associated valve 52 in closed position,the arm 54 being retained against rotation beyond a predeterminedposition by another stop 62 exible hose 40 having one end thereofcom--flcien't amount of fuel to provide a continuously burning pilot lightfor igniting the torch. The

hose 46' ismaintained in position adjacent the torch by a bracket 84'. l

Movement of the rod 56 and parts carried there- -by for operation of thevalves'52 is effected'by 4immediately to the right of the path 0f travelrespectively.

or the torch n, as shown in Fig'. 1. con springs 14 and 16 having oneend thereof secured to each of a pair of plates 18 and 88, respectively,fixed lto the plate 50, are attached at their opposite ends 'to an endof one of the levers 66 and 68, 5 respectively, each of which is urgedin a clockwise direction against an adjustable stop 62h and 62o,

'Ihe tensional strength of the springs 14 and 16 is substantially-equalbut Individually greater than the streng-th of the spring 1o im andtherefore the rod 56 is held in the position shown in'Fig. 2 and thevalves 52 are maintained closed.

From the foregoing it will be understood that the valves 52' arenormally retained in closed p0- l5 sition, as shown in Fig. 2, and aremoved to open position as hereinafter set forth. v

The work to be dried, herein illustrated u a mold 18', isprogressivelymoved in a direction parallel to the shaft I6 andimmediately below zo y the torch`32 by any suitable conveyor mechanism80', the speed of which may be adjusted to Dredetermine the exposure ofthemold to drying effect of the torch. As the mold approaches the pathof travel of the torch 32 the flask 82 contacts 25 thelever`68,\rotating it in a counter clockwise direction, against theaction of the spring 16, to

the position shown in full linsi' Fig. 2. However, the strength of thespring 58 is not sufficient to move the rod 54 to the right, as viewedin 3c: Fig. 2, by reason of the greater strength of the spring 14. 'Asthe mold is moved farther the flask 82 engages the lever 66 and thelatter is rotated in a counter Wclockwise direction, against' theactionofthe spring 14. When the levers 86 and 85 68 are thus' rotated "theforces of the-springs 14 and 16 on the rod 56 are released yand the rodis moved to the right, asviewed in Fig. 2, by the action of the spring58. This movement of the rod 56 rotates the arms 54, in a counterclockwise 40, directionby contact of each arm with a respective stop 62,and the valves 52 of the conduits 46 andi 42 are opened permitting asupply of fuel to pass to the torch 32, the latter being ignited by thepilot light. v4g

VThe mold is then swept by successive osciilaf tions of the flamefror'n'the torch until moved by t'ne 'conveyor to a position so that theiiasl:l 82 nolonger engages the lever 68 and the latter is returned bythe spring 16 to the position shown 'in 5c, dotted lines in Fig. 2. Thestrength of the spring 16 alone is suillcient to return the rod 56,against the action of the spring 58, to the position shown in Fig. 2thereby closingthe valves 52 prior to the time the flask is out ofengagement with the lever ,552.:

66. By so controlling operation of the valves 62 the torch is productiveof heat only during the time the internal surface of the mold is withinthe effective area of the llame,I and the operating Y period of thetorch may be made shorter than the 00,

Y time required for movement of the flask througha distance equal to itsover-al1 length. Opening of the valves 62 by contact of the mold flask82 with the levers 66 and 68 may be advanced or postponed by movement ofthe Mijnshble stop 62h' retaining the lever 66 against clockwise.direction. For instance, movement of the stop 62h in a direction to therlght,`as viewed in' Fig. 2, will rotate the lever 66 in a counterclock-'- wise direction to a position whereit will not con- I0A tact themold flask for opening the valves 62 until a predetermined portion ofthe mold has passed beyond the path of travel of the oscillating torchli during the time the latter is productive of heat.

WhatIclaimis:

1. Drying apparatus including a drying station, conveying mechanism forprogressively moving articles through said station, a torch oscillatablymounted in said station, and driving mechanism for oscillating saidtorch throughout a predetermined course.

2. Drying apparatus including a drying station, conveyingv mechanism forprogressively moving articles linearly through said drying station, anoscillatable torch in said station having an axis substantially parallelto the path of travel of said conveyor and having a ame course extendingtransversely of and in the path of movement of said articles, anddriving mechanism for oscillating said torch throughout a predeterminedarcuate course.

3. Drying apparatus including a drying station, conveying mechanism forprogressively moving articles linearly through said drying station, anoscillatable torch in said station having an axis substantially parallelto thepath of travel of said conveyor and having a flame courseextending transversely of and in the path of.movement of said articles,and driving mechanism for oscillating said torch throughout apredetermined arcuate course, said mechanism being adjustable to varythe length of the stroke of said torch,

Drying apparatus including a drying station, conveying mechanism forprogressively moving articles through said station, a heating ele-- mentoscillatably mounted in said station, valve mechanism controlling thesupply oi fuel to said element, and a control for said valve mechanismadapted to be actuated by engagement with an article during movementthereof by said conveyor.

5. Drying apparatus including a drying station, conveying mechanism forprogressively moving articles through said station, a heating elementoscillatably mounted in said station, valve mechanism controlling thesupply of fuel to said element, and a control for said valve mechanismadapted to be actuated by engagement with an article during movementthereof by said conveyor, said control being adjustable to open saidvalve when said article is in a predetermined position relative to saidtorch.

6. Drying apparatus including a plurality of drying stations, conveyingmechanism for progressively moving articles through said stations, a

heating element oscillatably mounted in each of said stations having anindividual valve mechanism and control therefor, driving mechanism forcontinuously'oscillating said heating elements throughout apredetermined arcuate course, said ing said elements, said mechanismbeing adjustable to predetermine the arcuate course of said elements forsubjecting a portion of a moving article to a heating element,individual valve mechanism and control therefor associated with 5 eachheating element, said elements being oper-l able intermittently forproducing a drying action by engagement of a 4moving article with saidvalve control, said control being adjustable for subjecting apredetermined portion of the moving l0 article to said heating elements.l 8. Drying apparatus adapted to operate in conjunction With a conveyingmechanism for progressively moving articles relative to said apparatus,an oscillatably mounted heating element, l5 driving mechanism forvcontinuously oscillating said element, a fuel supply system for saidelement including valve mechanism and a control therefor, said controlcomprising rotatably mounted members, means retaining said mem- 2o bersin a predetermined position closing said valve mechanism, said meansincluding resilient elements, said members being rotatable against theaction of said yieldable elements by engagement with a moving articlefor moving said valve 25 to open position.

9. A drying apparatus including an oscillatably mounted torch, conveyingmechanism for progressively moving articles into the path of. travel ofsaid torch, valve mechanism controlling the 3G supply of fuel to saidtorch, control for sai-d valve, mechanism operable by engagement with amoving article, said control being adjustable to open said valvemechanism when said article is in a predetermined position relative tosaid torch for 85 subjecting a selected portion or" said article todrying action, and driving mechanism for continuously oscillating saidtorch, said mechanism being adjustable for limiting the oscillatorystroke or said torch to a course conforming subn stantially to adimension of said article. 10. A drying apparatus including a drying station, conveying mechanism for progressively moving articles through saidstation, an oscillatably mounted heating element in said station, valvemechanism controlling the supply of fuel to said heating element,control apparatus normally retaining said valve mechanism in closedposition, said control apparatus including a member engageable by saidarticle for opening 50 said valve mechanism and another memberengageably by said article for closing said valve mechanism, saidmembers being so constructed and arranged as to initiate operation ofsaid heating element after a predetermined portion of the article hasmoved through the eiective range of said heating element and todiscontinue the operation of said heating element before a portion ofthe article has moved vvithin the effective range of said heatingelement.

ROBERT R. snow.

